Method and system for transferring a load in a thunder and lightning weather

Abstract

Provided are a load transfer method and system in thunder and lightning weather. The method includes: detecting lightning and predicting a position and time of a lightning strike to obtain a lightning prediction result; determining a transmission line possibly struck by lightning in a power grid according to the lightning prediction result; determining a load transfer scheme; and before the lightning occurs, transferring at least part of loads on the transmission line possibly struck by lightning according to the load transfer scheme.

What is claimed is: 
     
       1. A load transfer method in thunder and lightning weather, comprising:
 detecting lightning and predicting a position and time of a lightning strike to obtain a lightning prediction result; 
 determining a transmission line possibly struck by lightning in a power grid according to the lightning prediction result; 
 determining a load transfer scheme; and 
 before the lightning occurs, transferring at least part of loads on the transmission line possibly struck by the lightning according to the load transfer scheme; 
 
       wherein determining the load transfer scheme comprises:
 determining the load transfer scheme according to a classification result obtained by pre-classifying a plurality of loads in the power grid; and 
 
       wherein transferring the at least part of the loads on the transmission line possibly struck by the lightning comprises:
 transferring the at least part of the loads on the transmission line possibly struck by the lightning to at least one of the following: a standby transmission line, a distributed micro-grid or a power storage device. 
 
     
     
       2. The method of  claim 1 , after transferring the at least part of the loads on the transmission line possibly struck by the lightning to the standby transmission line, further comprising:
 in response to the lightning, transferring the remaining part of the loads on the transmission line to at least one of the following: the distributed micro-grid or the power storage device. 
 
     
     
       3. The method of  claim 2 , further comprising:
 after the lightning occurs, recovering the transferred loads to a state before the transferring in a case where the transmission line possibly struck by the lightning operates normally. 
 
     
     
       4. The method of  claim 1 , wherein pre-classifying the plurality of loads in the power grid comprises:
 classifying the plurality of loads in the power grid into primary loads, important loads and general loads according to significance; and 
 classifying customers in the power grid into a sort-I customer, a sort-II customer, a sort-III customer and a sort-IV customer according to loads owned by the customers in the power grid, wherein the sort-I customer is a customer who owns both primary loads and important loads, the sort-II customer is a customer who owns primary loads but does not own important loads, the sort-III customer is a customer who owns important loads but does not own primary loads, and the sort-IV customer is a customer who owns only general loads. 
 
     
     
       5. The method of  claim 4 , wherein determining the load transfer scheme according to the classification result comprises:
 transferring the primary loads owned by the sort-I customer and the primary loads owned by the sort-II customer to the standby transmission line, transferring at least one of important loads owned by the sort-I customer or general loads owned by the sort-II customer to at least one of the distributed micro-grid or the power storage device, and keeping loads owned by the sort-III customer and loads owned by the sort-IV customer unchanged. 
 
     
     
       6. The method of  claim 5 , wherein during determining the load transfer scheme, a part of primary loads owned by the sort-I customer and the sort-II customer is transferred to at least one of the distributed micro-grid or the power storage device in a case where remaining capacity of the standby transmission line is not enough to carry the primary loads owned by the sort-I customer and the sort-II customer. 
     
     
       7. The method of  claim 1 , wherein determining the transmission line possibly struck by the lightning in the power grid according to the lightning prediction result further comprises:
 determining an adjacent line of the transmission line possibly struck by the lightning in the power grid according to the lightning prediction result; and 
 wherein transferring the at least part of the loads on the transmission line possibly struck by the lightning comprises: 
 transferring the at least part of the loads on the transmission line possibly struck by the lightning to the adjacent line. 
 
     
     
       8. The method of  claim 7 , wherein determining the load transfer scheme comprises:
 taking the transmission line possibly struck by the lightning in the power grid and the adjacent line as adjustment objects, calculating and allocating a control quantity of each adjustment object according to a load condition on each adjustment object and a power flow control capability of a unified power flow controller (UPFC) facility corresponding to each adjustment object, and sending the control quantity of each adjustment object to the UPFC facility corresponding to a respective adjustment object; and 
 wherein before the lightning occurs, transferring the at least part of the loads on the transmission line possibly struck by the lightning according to the load transfer scheme comprises: 
 before the lightning occurs, performing, by the UPFC facility corresponding to the respective adjustment object, power flow adjustment of the respective adjustment object according to the received control quantity, to transfer the at least part of the loads on the transmission line possibly struck by the lightning to the adjacent line. 
 
     
     
       9. The method of  claim 8 , wherein during load transfer, a UPFC facility for controlling the transmission line possibly struck by the lightning outputs, according to the control quantity of the transmission line possibly struck by the lightning, a voltage whose phase lags behind a phase of an original line voltage of the transmission line possibly struck by the lightning, and a UPFC facility for controlling the adjacent line outputs, according to the control quantity of the adjacent line, a voltage whose phase leads ahead a phase of an original line voltage of the adjacent line. 
     
     
       10. The method of  claim 1 , further comprising:
 after the lightning occurs, determining whether the transmission line possibly struck by the lightning trips out, and recovering the transferred loads to a state before the transferring in a case where the transmission line possibly struck by the lightning does not trip out. 
 
     
     
       11. A load transfer system in thunder and lightning weather, comprising:
 a lightning detection module, which is configured to detect lightning; 
 a lightning prediction module, which is connected to the lightning detection module and configured to predict a position and time of a lightning strike to obtain a lightning prediction result; 
 a control and decision system, which is connected to the lightning prediction module and configured to determine a transmission line possibly struck by lightning in a power grid according to the lightning prediction result and determine a load transfer scheme; and 
 an executive system, which is connected to the control and decision system and configured to before the lightning occurs, execute the load transfer scheme to transfer at least part of loads on the transmission line possibly struck by the lightning; 
 
       wherein the control and decision system is configured to determine the load transfer scheme in the following way:
 determining the load transfer scheme according to a classification result obtained by pre-classifying a plurality of loads in the power grid; and 
 
       wherein the control and decision system is further configured to send out a control signal corresponding to the load transfer scheme, and the executive system comprises an executive module, wherein the executive module is connected to the control and decision system and the power grid and the executive module is configured to execute the load transfer scheme according to the control signal, to transfer the at least part of the loads on the transmission line possibly struck by the lightning to at least one of the following: a standby transmission line, a distributed micro-grid or a power storage device. 
     
     
       12. The system of  claim 11 , further comprising:
 a geographic information system, which is connected to the control and decision system and configured to provide the control and decision system with geographic information required in determining the transmission line possibly struck by the lightning in the power grid. 
 
     
     
       13. The system of  claim 11 , further comprising:
 a main-grid monitoring system, which is connected to the control and decision system and configured to provide the control and decision system with operation status data of the power grid; and 
 a micro-grid monitoring system, which is connected to the control and decision system and configured to provide the control and decision system with operation status data of the distributed micro-grid. 
 
     
     
       14. The system of  claim 11 , wherein the control and decision system is further configured to determine an adjacent line of the transmission line possibly struck by the lightning in the power grid according to the lighting prediction result; and wherein the executive system is further configured to transfer the at least part of the loads on the transmission line possibly struck by the lightning to the adjacent line. 
     
     
       15. The system of  claim 14 , wherein
 the executive system further comprises a plurality of unified power flow controller (UPFC) facilities, each of the plurality of UPFC facilities is connected to the control and decision system and is connected to a respective transmission line; 
 the control and decision system is further configured to, take the transmission line possibly struck by the lightning in the power grid and the adjacent line as adjustment objects, calculate and allocate a control quantity of each adjustment object according to a load condition on each adjustment object and a power flow control capability of a UPFC facility corresponding to each adjustment object, and send the control quantity of each adjustment object to the UPFC facility corresponding to a respective adjustment object; and 
 the UPFC facility corresponding to the respective adjustment object is configured to perform power flow adjustment of the respective adjustment object according to the received control quantity, to transfer the at least part of the loads on the transmission line possibly struck by the lightning to the adjacent line. 
 
     
     
       16. The system of  claim 14 , further comprising:
 a geographic information system, which is connected to the control and decision system and configured to provide the control and decision system with geographic information required in determining the transmission line possibly struck by the lightning in the power grid and the adjacent line. 
 
     
     
       17. The system of  claim 14 , further comprising:
 a power grid information system, which is connected to the control and decision system and configured to provide the control and decision system with power grid information and update power grid information under control of the control and decision system.